Academy Heroine's Right Diagonal Back Seat - Chapter 7

A veteran gamer finds himself in a world similar to the game he played.You say you need to learn skills by leveling up? Sorry, I already know all of them.You say you have to meditate to level up? Sorry, I only need to fight monsters for that.

I couldn’t even clear the 2D version, now to clear the game in reality?Maybe I’ll have to live here for the rest of my life.Well, even that won’t be easy.– A player found himself in the game, Dungeon and Stone, as a savage barbarian.To keep his secret, he must become the mask – must make himself be seen as more savage, more fearless than any others – a paragon of his race in the eyes of the whole world.Back on earth, in the empty darkened room, the quiet computer again began to whir. Text began to appear on the black screen.「Synchronization complete. 」

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

In the 21st century Earth gave Birth to greatest genius ever. A genius who Master myriad of arts. Medicine to Engineering. Mathematics to Micro Biology. Weapon Designing to Environmental control. Music to Painting. Dance to Martial arts. He mastered Everything.